Method of preparing metalloorganic compounds



Patented Jan.- 14,1941 7 v UNITED STATES METHOD OF PREPARING METALLO- ORGANIC COMPOUNDS George H. Denison, Jr., Berkeley, and Arthur C. Ettling, Richmond, Calif., assignors to Standard Oil Company of California, San Francisco, Calif., a corporation of Delaware No Drawing. Application October 4, 1938, Serial No. 233,326

20 Claims.

This invention relates to methods of preparing metal compounds of organic acids and involves. as a preferred group, the preparation of metal salts of high molecular weight organic acids.

Methods utilized heretofore in the preparation of metalsalts of high molecular weight organic acids have involved'various diiliculties. This is particularly true where metal salts of relatively weak bases, such as the alkaline earth metals and/or high molecular weight water-insoluble organic acids, are involved. Often expensive raw materials have been required and extended purification methods were necessary to obtain the F product of the desired purity and characteristics.

For example. when salts of high molecular weight water-insoluble organic acids are prepared by double decomposition in the presence of an aqueous media, various undesirable reaction products v are sometimes separable only after extended washing or other purification steps.

Additional difliculties have been encountered where the metallic compound of the high molecularrweight organic acids is amorphous or has a high melting point. It has been found, for in stance, that when water is present during preparation of such compounds, the salts tend to hold the water so intimately that it can be subsequently removed only by heating to such high temperatures as will partially decompose or deteriorate the compound. The water formed by reaction of an hydroxide with an acidic hydrogen, as in some prior proposed methods of preparation, is found to introduce this difliculty and materially alter the solubility of the salt in organic solvents such as petroleum hydrocarbons. The amount of water necessary to materially alter the solubility or other properties or these compounds is, in some instances, quite small.

We have discovered that metal compounds of organic acids can be advantageously prepared by reacting, in a non-aqueous environment, a carbide of ametal and the organic acid. This process is particularly advantageous when applied to high molecular weight organic acids. Despite the fact that the high molecular weight organic acids are extremely weak and in general relatively unreactive, their metal salts have been obtained in an anhydrous and relatively pure condition. High yields of the desired icompounds have been obtained by using relatively cheap raw materials where prior known processes either gave a less desirable product or required more expensive reagents as starting materials.

Accordingly, an object of the invention is to provide an improved method of preparing metallic compounds of organic acids.

Another object the invention is to produce metallic salts of high molecular weight organic acids by an improved process which gives a high yield of a product that is relatively free from inorganic salts and aqueous contaminations.

A further object is to provide a process which enables one to readily 'produce metallic salts of very weak organic acids and of metals having relatively weak basic characteristics.

An additional object of the invention is to provide a process which avoids the use of aqueous solutions or the presence of water in the production of metallic salts of water-insoluble high molecular weight organic acids.

The term organic acids is used herein to designate acids containing an organic substituent and does not preclude the presence of inorganic components in addition to carbon, hydro-' gen and oxygen present in all organic acids. The term high molecular weight organic acids" is intended to designate acids having a ,molecular weight more than approximately 100.

Examples of acids which are to be regarded as organic acids within the meaning of this term, as herein used, and which fall within the broad scope of the present invention comprise substituted acids of phosphorus containing an organic substituent, substituted sulfuric acids, substituted acids of arsenic, sulfonic acids, carbocyclic carboxylic acids, and aliphatic carboxylic acids.

,The following comprise examples or substituted acids of phosphorus which may be used in the present process:

H ROP0H Monocstcr of orthophosphoric acid ll R0P-OH Dl-cstcr or orthophosphorlc acid Phosphonous acid Mono-ester of phosphonous acid Phosphinous acid Pbosphonic acid Monoester of phosphonic acid P-OH B4) lbocphiuic acid In. the above formulae R may be alkyl, aryl, alkar'yl, aralkyl or cyclic non-benzenoid groups.

Similarly, a corresponding series of substituted sulfurous' or sulfuric acids or partially esterified sulfur containing acids, such .as sulfuric acids, are contemplates as falling within the broad scope of the invention and the term "organic acids."

clei, e. g. aryl, alkaryl, aralkyl or cyclic nonbenzenoid types. Examples of such acids comprise. phenyl stearic acid,- naphthenic acids, naphthoic acids, benzoic acid, and the like. The process is also applicable to high molecular weight aliphatic acids such as stearichpalmitic. myristic, lauric and oleic acids.

The process of the invention is particularly suited for and finds a most useful application in the preparation of metal salts of water-insoluble phenols. Specific examples of suitable water-insoluble phenols comprise the alkyl phenois such as p-octyl phenol, p-lauryl (dodecyl) phenol and p-cetyl phenol.

It is to be understood that the process is applicable to the preparation of metal salts of other high molecular weightwater-insoluble substituted phenols which contain an aromatic hydroxy group, i. e. an OK groupdirectly connected to a benzene ring, and in which other substituents on the ring may be alkyl, aryl. alkaryl, aralkyl or cyclic non-benzenoid groups. Likewise polyhydroxy phenols and phenols containing conjugated benzene rings may be utilized as an acid constituent in the formation of the metal salts involved herein. The term a phenol" or phenolic compound is used in the present specification to designate, generically, the above types of phenols which are characterized by an acid group comprising one or more on radicals directly attached to an aromatic nucleus.

As a specific example of a phenol useful in the present process and a method of preparing the same, the following is given:

Phenol and a butene polymer, having an appolymerization of a mixture of butenes containing butene-l, butene-2, and iso-butene, were mixed. To this mixture, containing 237 grams of phenol and 500 grams of the above mentioned butene polymers, 140 cubic centimeters of 94% sulfuric acid was added slowly with agitation. The temperature was kept below 65 F. during addition of the acid. The mixture was agitated for two hours after the addition of acid was completed and permitted to come to room temperature. The reaction product was then diluted with an equal volume. of water and placed in a sealed autoclave where it was heated at 350' F.

I for an hour with agitation. The product was washed with water, 5% sodium carbonate solu- ,alkyl phenol is as follows:

511 grams of crude cresylic acid, 900 grams of 1 an oleflne polymer containing an average of 14 carbon atoms per molecule and 475 grams of 98% sulfuric acid were utilized in preparing an alkyl cresol. The ingredients were mixed, the temperature controlled and the product washed as in the previous example. The reaction product was vacuum distilled at lO'miilimeters and a 50 to cut separated. Thisportlon of the distillate had a molecular weight of 291 and was used to prepare the calcium salt described in Example 6 hereinafter.

The above. methods of preparing the alkyl phenols suitable for the purpose of this invention are merely illustrative. For example: other condensation reactions utilizingalcohols or alkyl chlorides rather than oleflnes as starting materials may be adopted for introducing an alkyl group into the aromatic nucleus. Also other known condensation agents such as aluminum chloride, zinc chloride and the like may be utilized to effect the alkylation of the phenol. A mixture ofsulfurlc and glacial acetic acids may be used with advantage as a condensing agent.

A suitable mixture comprises 100 parts by weight 98% H3804 to 60 parts by weight of glacial acetic acid. The presence of the acetic acid facilitates temperature control and gives a softer, easier handled reaction product.

60 As has been previously indicated, metal salts of high molecular weight'organic acids can be advantageously prepared by directly reacting the acid with a carbide of a metal. Suitable metal carbides are those which react with water to form acetylene. V

The following comprise illustrative examples of processes utilizing the principles of this invention:

Example 1.-247 grams of an alkylated phenol having an apparent molecular weight of 247 were agitated for six hours at 500 F. with 64 grams of powdered calcium carbide. A gaseous reaction product containing acetylene was formed and removed. The product remaining in the reaction zone was a dark colored brittle solid at room temperature and comprised a calcium salt of the alkylated phenol. 94% of the theoretical yield of calcium alkyl phenate was obtained as shown by an analysis of a sample of the reaction product freed from calcium carbide by hitration of its petroleum ether solution.

" Example 2.-685 grams of an alkylated phenol having an apparent molecular weight of 290 were agitated for six hours at from approximately 500 F. to 540 F. with 9%) grams of calcium carbide. A gas containing acetylene was formed and removed. The product remaining in the reaction zone was a dark colored brittle solid at room temperature. A yield of calcium alkyl phenate, representing .9692 of that theoretically possible, was obtained.

The reactions occurring in the examples above disclosed may be represented by the following equation:

In the above equation R represents an alkyl group but may be aryl, alkaryl, aralkyl or cyclic non-benzenoid groupsas heretofore explained. Metal carbides other than calcium carbide give the above type reaction and may be utilized.

Emmple '3.-To 267 grams of mono-cetyl' phosphoric acid were added slowly and with agitation v100 grams of finely powdered calcium carbide. The temperature was held at 200 F. and the addition of the carbide carefully controlled to avoid excess tendency to foam. The total time for completion of the reaction was one hour. The product was freed of excess calcium carbide by dissolving in di-ethyl ether, filtering and evaporating oil the ether. showed complete conversion of the mono-cetyl phosphoric acid to calcium cetyl phosphate.

An example of the preparation of metal salts of carbocyclic carboxyllc water-insoluble organic acids is as follows:

Example 4.-'-To 684 grams of naphthenic acid obtained from a California fuel oil fraction were added 75;grams of powdered calcium carbide. The mixture was heated in a flask with a' stirrer to 350 F. The temperature then rose rapidly due to heat of reaction to 390 F., and the mixture remained at that temperaturefor some time. The mixture was then allowed to cool to 350 F. and was held at that temperature for two hours. A yield of approximately 90% of calcium naphthenate was obtained and dissolved in a mineral lubricating oil fraction consisting of S. A. E. 30 acid refined Western oil. This solution was filtered to remove unreacted calcium v carbide. The calcium naphthenate obtained was soluble in mineral oil in all proportions, and in concentrations of l to 2% in oil did not materially increase the viscosity of the oil or cause gel formation. Calcium naphthenate prepared in an aqueous environment is soluble in oil in only comparatively small proportions and causes gel formation when added to lubricating oils in amounts as low as 2%.

Further examples of preparation of calcium salts of various phenols are as follows:

Example 5-44 grams of p-cyclohexyl phenol and grams of powdered calcium carbide were heated together at 350 F. for one hour. A tan colored powder was obtained as a product which was insoluble in petroleum ether and soluble in terials being reacted. Atmospheric to react with water to of reaction, and in Analysis for calcium 3 benzene. This product was the calcium salt of the cyclohexyl phenol. I

Ezample 6.234 grams of an alleyl cresol (molecular 'weight 291) and grams of powdered calcium carbide were heated ring for four hours. The product is tle solid, soluble in mineral oil.

Any of the reactions herein disclosed may be carried out in the presence of a non-aqueous, inert solvent such asa hydrocarbon diluent like petroleum naphtha or mineral lubricating oil. The presence of substantial quantities of water in thereactlon zone should beavoided. The conditions under which the reaction is carried out may be altered materially, depending upon the time allowed for the reaction and upon the mapressure is preferred but the invention does not preclude the use of either sub-atmospheric or super-atmospheric pressures in the reaction zone. The temperature required is a function of the metal carbide utilized and of the organic acid being rea hard britat 530 F. with stiracted. Elevated temperatures increas the rate general, temperatures above 200- F. are preferred, and in the case of the less reactive substituted phenols, such as octyl and cetyl phenols, temperatures above approximately 400 F. are preferred. Intimate contact between the reacting ingredients promotes the reaction, and the metal carbide should preferably be added in powdered or granulated form in order that it may be intimately contacted with the organic acid by agitation.

It has been observed that methyl alcohol tends to promote the reaction of calcium carbide with the high molecular weight alkyl phenols, and such an alcohol may be incorporated in the reaction zone.

The process of this invention has a number of' advantages. It avoids the use of an aqueous 501- vent as a medium for effecting the reactions and. as previously noted, thereby precludes dimculties often encountered by reasonof impurities or hydrolysis of the reaction product. One could not predict that the high molecular weight organic acids, which are relatively stable and unreactive, would react with calcium carbide and the like in non-aqueous media. Another advantage of the process is that acetylene rather than water is formed by the reaction of the two initial components and that this gas is easily removed without undue contaminationor modification of the finished product. This last feature is of particular utility in that the necessity for removing substantial amounts of reaction products comprising inorganic salts and/or water is avoided. Other advantages of the process to those skilled in. the art.

In the present specification and claims the term high molecular weight organic acids is intended to designate acids having a. molecular weight greater than approximately 100, as previ-' larly applicable to compounds 'of the phenolic type.

While the character of the invention has been described in detail, and numerous examples of the preparation and application of the process given, this has been done by way of illustration will be apparent.

weight water-inshould be imposed upon the invention thereby. It will be apparent to those skilled in the art that numerous modifications and variations of the illustrative examples may be effected in the practice of the invention, which is of the scope of the claims appended hereto.

We claim:

,1. A process of preparing a metal compound of an organic acid, which comprises directly reacting a metal carbide with said organic acid in an environment substantially free of water, whereby said metal compound and a gaseous reaction product are formed and recovering the metal com-pound formed by the reaction.

2. A process of preparing a metal compound. of a high molecular weight organic acid, which comprises directly reacting a metal carbide with an organic acid having a molecular weight greater than approximately 100 in an environment substantially free from water, whereby said metal compound and a gaseous reaction product areformed.

3. A process of preparing metal salts of carbocyclic organic acids, which comprises directly reacting an acetylide with a carbocyclic organic acid in an environment substantially free of water, whereby said metal salt and acetylene are "formed.

4.. -A process of preparing metal salts of carbocyclic carboxylic acids, which comprises directly reacting an acetylide with a water-insoluble carbocyclic carboxylic acidin an environment substantially free of water, whereby said metal salt and acetylene are formed.

5. A process of preparing metal salts of naphthenic acids, which comprises directly reacting an acetylide with a naphthenic acid in an environment substantially free of water and removing the gaseous reaction product. whereby said metal salt is formed in the reaction zone.

6. A process of preparing metal salts of organic acids of phosphorus, which comprises directly reacting an acetylide with an organic acid of phosphorus in an environment substantially tree of water, whereby said metal salt is formed in the reaction zone.

7. A process as in claim 1, in which the reaction is carried out in the presence of an inert diluent.

8. A process as in claim -1, in which the reaction is carried out in the presence of a hydrocarbon solvent.

9. A process as in claim 1, in which the reaction is carried out in the presence of methyl alcohol.

10. A procm of preparing a metal salt of an organic acid, which comprises directly reacting a carbide of an alkaline earth metal with an organic acid and removing the gaseous reaction product, whereby said metal salt is formed in the reaction zone.

11. A process of preparing metal salts of waterinsoluble carbocyclic organic acids, which comprises directly reacting a carbide of an alkaline earth metal with a water-insoluble carbocyclic organic -acid, removing the gaseous reaction product, whereby said metal salt is formed in the reaction zone.

only and with the intention that no limitation 12. A process of preparing metal-salts of waterinsoluble carbocyclic carboxylic acids, which comprises directly reacting a carbide of an alkaline earth metal with a water-insoluble carbocyclic carboxylic acid in an environment substantially free of water and removing the gaseous reaction product, whereby said metal salt is formed in the reaction zone.

13. A process of preparing metal salts of naphthenic acids, which comprises directly reacting a carbide of an alkaline earth metal with a naphthenic acid in an environment substantially free f water and removing the gaseous reaction product, whereby said metal salt is formed in the reaction zone.

14. A process of preparing metal salts of water-insoluble organic acids of phosphorus, which comprises directly reacting a carbide of a metal with an organic acid of phosphorus in an environment substantially free of water and removing the gaseous reaction product, whereby said metal salt is formed in the reaction zone.

15. A process of preparing a metal salt of water-insoluble organic acids, which comprises directly reacting calcium carbide with an organic acid in an environment substantially free of water, and removing the gaseous reaction product, whereby said metal salt remains in the reaction zone.

16. A process of preparing metal salts of waterinsoluble carbocyclic organic acids, which comprises directly reacting calcium carbide with a water-insoluble carbocyclic organic acid in an environment substantially free of water and removing the gaseous reaction product, whereby said metal salt is formed in the reaction zone.

17. A process of preparing metal salts of waterinsoluble carbocyclic carboxylic acids, which comprises directly reacting calcium carbide with a water-insoluble carbocyclic carboxylic acid in an environment substantially free of water and removing the gaseous reaction product, whereby said metal salt remains in the reaction zone.

18. A process of preparing metal salts or water-insoluble organic acidsof phosphorus, which comprises directly reacting calcium carbide with a water-insoluble organic acid of phosphorus in an environment substantially free of water and removing the gaseous reaction product. whereby said metal salt is formed in the reaction zone.

19. A process of preparing a metallo-organic compound which comprises directly reacting an acetylide with an organic acid in an environment substantially free of water to form a metal salt of said acidic compound and a hydrocarbon gas in the reaction zone, and removing the'gaseous reaction product.

20. A process of preparing a metal salt of a substantially water-insoluble organic acid which comprises reacting an acetylide with an organic acid in an environment substantially free of water to form a metal salt of said acid and a hydrocarbon gas in the reaction zone, removing the gaseous reaction product, and recovering the salt of said acid formed by said reaction.

GEORGE H. DENISON, J a. ARTHUR C. E'I'I'LING. 

